Rotary mowing machines can have a transverse support attached by a towing bar to a tractor and oriented at an angle to the travel direction and a plurality of mowing drums, parallel to one another under the transverse support and rotatable on it. They are offset from one another in the travel direction and their working zones overlap.
Rotary mowing implements are used particularly in hay harvesting, wherein the dried hay or crop must be formed in a swath. With the mowing drums driven in the same rotational direction on a bar inclined with respect to the travel direction, the dried hay or crop is conveyed along the entire width of the side-by-side mowing drums and form a swath or windrow beside the final mowing drum. This kind of comparatively large swath or windrow can be picked up subsequently by a transport vehicle. The advantage of a rotary mowing attachment as opposed to a hay harvesting machine with raking wheels is that the once cut hay or crop is carefully handled, because of the elastic structure of the mowing drum, which, for example, can comprise rubber members, and also because of the lack of metal teeth which can be broken off and can damage the subsequent further processing machines and which can ultimately reach the cattle or other animals.
In U.S. Pats. Nos. 4,269,019 and 4,030,275 the structure of such mowing drums is described.
These mowing drums generally comprise a cylindrical portion attached above an outwardly flared skirt which has a plurality of cutting blades. These drums rotate about a central shaft attached to a generally circular slide disk or convex plate positioned below the flared skirt with the cutting blades so as to keep the blades from the ground. Both these above mentioned prior art patents describe inventive structures applicable to a single mowing drum which assist the mower in properly forming a swath or windrow. U.S. Pat. No. 4,269,019 describes a plurality of tines which are attachable horizontally to the cylindrical portion of a mowing drum to help ted the crop. U.S. Pat. 4,030,275 describes a flap or deflection plate attached adjacent the mowing drum to help form a proper swath or windrow and an improved flared skirt having a plurality of ridges which pass adjacent the lower edge of the deflection plate, wherein the ridges form an acute angle with the deflection plate when viewed from above down the rotation axis of the mowing drums. The ridge structure assists in preventing troublesome clogging of crop or hay between the deflector plate and the flared skirt.
A hay or crop harvesting machine with a pair of raking wheels, which are supported by means of rollers movable on the ground, these wheels being mounted at the ends of a cross bar arm swingable in a horizontal plane and driven about vertically oriented axes, is taught in Swiss Pat. No. 499 254.
In this hay harvesting machine a first raking wheel is fixed with respect to the travel path of the hay harvesting machine, while a second raking wheel is shiftable from one side of the first raking wheel to the other side of the first raking wheel by means of a cross bar arm and on each side the second raking wheel is securable in position. So when the second raking wheel is pivoted to the first side position, each raking wheel works independently, that is, it can form at low rotary speed two swaths or bundles or at high rotary speed it turns over the product, while, when the second raking wheel is swung out to the second side position both raking wheels cooperate, so that the crop or hay cuttings are directed from the first raking wheel to the second, whereby a single correspondingly larger swath is formed.
For the shifting of the second raking wheel, however, the entire transverse support, to which both raking wheels are associated, must be pivoted about its pivot axis in a horizontal plane behind the tractor.
Dispensing with metallic teeth, which have several inherent disadvantages, in these known hay harvesting machines, the raking wheels are movable each by a supporting roller on the ground, which with an arm are pivotally supported on a bracket, wherein the rear raking wheel must be provided with an additional trailer roller or caster, which is attached with an attachment member to the bracket. In pivoting of the arm with both raking wheels attached to it, in order that the supporting rollers of the rear raking wheel be put in the new working position parallel to the longitudinal travel axis, the position locking mechanism of the positioning segments of the rear raking wheels on the cross bar arm must be correspondingly changed.